The Hoop Tech 5 "x 3" Window Set for Slim Line 1 Clamping System is the most popular shallow pocket window size for clamp owners. The Hoop Tech 5 "x 3" Window Set for Slim Line 1 Clamping System works well on shallow pockets and along the edges of bags. The Hoop Tech 5 "x 3" Window Set for Slim Line 1 Clamping System is also popular for straps, dog collars, name tags, and karate belts.